2-(substituted phenyl)-6-hydroxy or alkoxy-5-substituted-4-pyrimidinecarboxylates and their use as herbicides

ABSTRACT

2-(Substituted phenyl)-6-hydroxy or alkoxy-5-substituted-4-pyrimidinecarboxylic acids and their derivatives are herbicides demonstrating a broad spectrum of weed control.

BACKGROUND OF THE INVENTION

This application claims the benefit of U.S. Provisional Application Ser.No. 61/124,695 filed on Apr. 18, 2008. This invention relates to2-(substituted phenyl)-6-hydroxy oralkoxy-5-substituted-4-pyrimidinecarboxylic acids and their derivativesand to the use of these compounds as herbicides.

A number of pyrimidinecarboxylic acids and their pesticidal propertieshave been described in the art. U.S. 2007/0197391 A1 and U.S. Pat. No.7,300,907 B2 generically disclose2-substituted-6-amino-4-pyrimidinecarboxylic acids and their derivativesand their use as herbicides. U.S. 2009/0043098 describes certain2-substituted-1,6-dihydro-6-oxo-4-pyrimidinecarboxylic acids and theiruse in preparing 2-substituted-6-amino-4-pyrimidinecarboxylic acids.

SUMMARY OF THE INVENTION

It has now been found that 2-(substituted phenyl)-6-hydroxy oralkoxy-5-substituted-4-pyrimidinecarboxylic acids and their derivativesare herbicides with a broad spectrum of weed control against broadleafweeds as well as grass and sedge weeds and with excellent cropselectivity at low use rates. The compounds further possess excellenttoxicological or environmental profiles.

The invention includes compounds of Formula I:

wherein

Q represents a halogen, cyano, C₁-C₄ alkyl, C₁-C₄ haloalkyl, C₂-C₄alkenyl and epoxides thereof, C₂-C₄ haloalkenyl and epoxides thereof,C₂-C₄ alkynyl, C₂-C₄ haloalkynyl, C₁-C₄ alkoxy, C₁-C₄ haloalkoxy, C₁-C₄alkylthio or C₁-C₄ haloalkylthio;

R₁ represents H or C₁-C₄ alkyl;

W represents H or halogen;

X represents H or halogen;

Y represents halogen, C₁-C₄ alkyl, C₁-C₄ alkoxy, C₁-C₄ alkylthio, C₁-C₄haloalkyl, C₁-C₄ haloalkoxy, C₁-C₄ haloalkylthio, —NR₂R₃, C₁-C₄alkoxy-substituted C₁-C₄ alkyl, C₁-C₄ haloalkoxy-substituted C₁-C₄alkyl, C₂-C₄ alkenyl, C₂-C₄ haloalkenyl or C₁-C₄ haloalkyl-substitutedcarbonyl;

Z represents halogen, C₁-C₄ alkyl or C₁-C₄ haloalkyl; and

R₂ and R₃ independently represent H or C₁-C₄ alkyl; and agriculturallyacceptable derivatives of the carboxylic acid group.

Preferred compounds of formula (I) independently include those in whichQ represents Cl, Br, C₂-C₄ alkenyl or C₁-C₄ alkoxy; R₁ represents H; Wrepresents H; X represents H or F; Y represents F or OCH₃; and Zrepresents Cl.

The invention includes herbicidal compositions comprising anherbicidally effective amount of a compound of Formula I andagriculturally acceptable derivatives of the carboxylic acid group inadmixture with an agriculturally acceptable adjuvant or carrier. Theinvention also includes a method of use of the compounds andcompositions of the present invention to kill or control undesirablevegetation by application of an herbicidal amount of the compound to thevegetation or to the locus of the vegetation as well as to the soilprior to emergence of the vegetation.

DETAILED DESCRIPTION OF THE INVENTION

The herbicidal compounds of the present invention are derivatives of2-(substituted phenyl)-6-hydroxy-5-substituted-4-pyrimidinecarboxylicacid:

wherein

Q represents a halogen, cyano, C₁-C₄ alkyl, C₁-C₄ haloalkyl, C₂-C₄alkenyl and epoxides thereof, C₂-C₄ haloalkenyl and epoxides thereof,C₂-C₄ alkynyl, C₂-C₄ haloalkynyl, C₁-C₄ alkoxy, C₁-C₄ haloalkoxy, C₁-C₄alkylthio or C₁-C₄ haloalkylthio;

W represents H or halogen;

X represents H or halogen;

Y represents halogen, C₁-C₄ alkyl, C₁-C₄ alkoxy, C₁-C₄ alkylthio, C₁-C₄haloalkyl, C₁-C₄ haloalkoxy, C₁-C₄ haloalkylthio, —NR₂R₃, C₁-C₄alkoxy-substituted C₁-C₄ alkyl, C₁-C₄ haloalkoxy-substituted C₁-C₄alkyl, C₂-C₄ alkenyl, C₂-C₄ haloalkenyl or C₁-C₄ haloalkyl-substitutedcarbonyl;

Z represents halogen, C₁-C₄ alkyl or C₁-C₄ haloalkyl; and

R₂ and R₃ independently represent H or C₁-C₄ alkyl.

The hydroxy group at the 6-position of the pyrimidine ring can beunsubstituted or substituted with a C₁-C₄ alkyl substituent. The hydroxygroup can be further derivatized as an ester, a carbamate, a carbonate,a sulfonic ester or a phosphate ester. Such derivatives are capable ofbreaking down into the hydroxy group.

The carboxylic acids of Formula I are believed to be the compounds thatactually kill or control undesirable vegetation and are typicallypreferred. Analogs of these compounds in which the acid group of thepyrimidine carboxylic acid is derivatized to form a related substituentthat can be transformed within plants or the environment to an acidgroup possess essentially the same herbicidal effect and are within thescope of the invention. Therefore, an “agriculturally acceptablederivative”, when used to describe the carboxylic acid functionality atthe 4-position, is defined as any salt, ester, acylhydrazide, imidate,thioimidate, amidine, amide, orthoester, acylcyanide, acyl halide,thioester, thionoester, dithiolester, nitrile or any other acidderivative well known in the art which (a) does not substantially affectthe herbicidal activity of the active ingredient, i.e., the2-(substituted phenyl)-6-hydroxy oralkoxy-5-substituted-4-pyrimidinecarboxylic acid, and (b) is or can behydrolyzed, oxidized or metabolized in plants or soil to the2-(substituted phenyl)-6-hydroxy oralkoxy-5-substituted-4-pyrimidinecarboxylic acid that, depending uponthe pH, is in the dissociated or the undissociated form. The preferredagriculturally acceptable derivatives of the carboxylic acid areagriculturally acceptable salts, esters and amides.

Suitable salts include those derived from alkali or alkaline earthmetals and those derived from ammonia and amines. Preferred cationsinclude sodium, potassium, magnesium, and aminium cations of theformula:

R₄R₅R₆NH⁺

wherein R, R₅ and R₆ each, independently represents hydrogen or C₁-C₁₂alkyl, C₃-C₁₂ alkenyl or C₃-C₁₂ alkynyl, each of which is optionallysubstituted by one or more hydroxy, C₁-C₄ alkoxy, C₁-C₄ alkylthio orphenyl groups, provided that R₄, R₅ and R₆ are sterically compatible.Additionally, any two of R, R₅ and R₆ together may represent analiphatic difunctional moiety containing 1 to 12 carbon atoms and up totwo oxygen or sulfur atoms. Salts of the compounds of Formula I can beprepared by treatment of compounds of Formula I with a metal hydroxide,such as sodium hydroxide, or an amine, such as ammonia, trimethylamine,diethanolamine, 2-methylthiopropylamine, bisallylamine,2-butoxyethylamine, morpholine, cyclododecylamine, or benzylamine. Aminesalts are often preferred forms of the compounds of Formula I becausethey are water-soluble and lend themselves to the preparation ofdesirable aqueous based herbicidal compositions.

Suitable esters include those derived from C₁-C₁₂ alkyl, C₃-C₁₂ alkenylor C₃-C₁₂ alkynyl alcohols, such as methanol, iso-propanol, butanol,2-ethylhexanol, butoxyethanol, methoxypropanol, allyl alcohol, propargylalcohol or cyclohexanol. Esters can be prepared by coupling of the2-(substituted phenyl)-6-hydroxy oralkoxy-5-substituted-4-pyrimidinecarboxylic acid with the alcohol usingany number of suitable activating agents such as those used for peptidecouplings such as dicyclohexylcarbodiimide (DCC) or carbonyl diimidazole(CDI), by reacting the corresponding acid chloride of 2-(substitutedphenyl)-6-hydroxy or alkoxy-5-substituted-4-pyrimidinecarboxylic acidwith an appropriate alcohol, by reacting the 2-(substitutedphenyl)-6-hydroxy or alkoxy-5-substituted-4-pyrimidinecarboxylic acidwith an appropriate alcohol in the presence of an acid catalyst or bytransesterification. Suitable amides include those derived from ammoniaor from C₁-C₁₂ alkyl, C₃-C₁₂ alkenyl or C₃-C₁₂ alkynyl mono- ordi-substituted amines, such as but not limited to dimethylamine,diethanolamine, 2-methylthiopropylamine, bisallylamine,2-butoxyethylamine, cyclododecyl-amine, benzylamine or cyclic oraromatic amines with or without additional heteroatoms such as but notlimited to aziridine, azetidine, pyrrolidine, pyrrole, imidazole,tetrazole or morpholine. Amides can be prepared by reacting the2-(substituted phenyl)-6-hydroxy oralkoxy-5-substituted-4-pyrimidinecarboxylic acid chloride, mixedanhydride, or carboxylic ester of Formula I with ammonia or anappropriate amine.

The terms “alkyl”, “alkenyl” and “alkynyl”, as well as derivative termssuch as “alkoxy”, “acyl”, “alkylthio” and “alkylsulfonyl”, as usedherein, include within their scope straight chain, branched chain andcyclic moieties. The terms “alkenyl” and “alkynyl” are intended toinclude one or more unsaturated bonds.

Unless specifically limited otherwise, the term “halogen” includingderivative terms such as “halo” refers to fluorine, chlorine, bromine,and iodine.

The compounds of Formula I can be made using well-known chemicalprocedures. Many procedural details for making compounds of Formula Ican be found in the following patent and patent publication: U.S. Pat.No. 7,300,907 B2 and U.S. 2009/0043098. Intermediates not specificallymentioned in the above patent applications are either commerciallyavailable, can be made by routes disclosed in the chemical literature,or can be readily synthesized from commercial starting materialsutilizing standard procedures.

As shown in Scheme 1, the 2-(substitutedphenyl)-6-hydroxy-5-substituted-4-pyrimidinecarboxylic acid esters ofFormula I can be prepared by nitrous acid mediated hydrolysis of the6-amino compound of Formula II.

The method of Scheme 1 is illustrated in Examples 1 and 4.

Alternately, as shown in Scheme 2 compounds of Formula I may be preparedfrom compounds of Formula III by halogenation with typical reagents,such as the bromine, chlorine or N-halosuccinimides. The method ofScheme 2 is illustrated in Example 3.

It is recognized that some reagents and reaction conditions disclosedherein or in the chemical literature for preparing compounds of FormulaI may not be compatible with certain functionalities present in theintermediates. In these instances, the incorporation ofprotection/deprotection sequences or functional group interconversionsinto the synthesis will aid in obtaining the desired products. The useand choice of the protection groups will be apparent to one skilled inchemical synthesis.

One skilled in the art will recognize that, in some cases, after theintroduction of a given reagent as disclosed herein or in the chemicalliterature, it may be necessary to perform additional routine syntheticsteps not described in detail to complete the synthesis of compounds ofFormula I. One skilled in the art will also recognize that it may benecessary to perform a combination of the steps disclosed herein or inthe chemical literature in an order other than that implied by theparticular sequence presented to prepare the compounds of Formula I.

Finally, one skilled in the art will also recognize that compounds ofFormula I and the intermediates described herein or in the chemicalliterature can be subjected to various electrophilic, nucleophilic,radical, organometallic, oxidation, and reduction reactions to addsubstituents or modify existing substituents.

The compounds of Formula I have been found to be useful as pre-emergenceand post-emergence herbicides. They can be employed at non-selective(higher) rates of application to control a broad spectrum of thevegetation in an area or at lower rates of application for the selectivecontrol of undesirable vegetation. Areas of application include pastureand rangelands, roadsides and rights of way, power lines and anyindustrial areas where control of undesirable vegetation is desirable.Another use is the control of unwanted vegetation in crops such as corn,rice and cereals. They can also be used to control undesirablevegetation in tree crops such as citrus, apple, rubber, oil palm,forestry and others. It is usually preferred to employ the compoundspostemergence. It is further usually preferred to use the compounds tocontrol a wide spectrum of woody plants, broadleaf and grass weeds, andsedges. Use of the compounds to control undesirable vegetation inestablished crops is especially indicated. While each of the2-(substituted phenyl)-6-hydroxy oralkoxy-5-substituted-4-pyrimidine-carboxylate compounds encompassed byFormula I is within the scope of the invention, the degree of herbicidalactivity, the crop selectivity, and the spectrum of weed controlobtained varies depending upon the substituents present. An appropriatecompound for any specific herbicidal utility can be identified by usingthe information presented herein and routine testing.

The term herbicide is used herein to mean an active ingredient thatkills, controls or otherwise adversely modifies the growth of plants. Anherbicidally effective or vegetation controlling amount is an amount ofactive ingredient which causes an adversely modifying effect andincludes deviations from natural development, killing, regulation,desiccation, retardation, and the like. The terms plants and vegetationinclude germinant seeds, emerging seedlings and established vegetation.

Herbicidal activity is exhibited by the compounds of the presentinvention when they are applied directly to the plant or to the locus ofthe plant at any stage of growth or before planting or emergence. Theeffect observed depends upon the plant species to be controlled, thestage of growth of the plant, the application parameters of dilution andspray drop size, the particle size of solid components, theenvironmental conditions at the time of use, the specific compoundemployed, the specific adjuvants and carriers employed, the soil type,and the like, as well as the amount of chemical applied. These and otherfactors can be adjusted as is known in the art to promote non-selectiveor selective herbicidal action. Generally, it is preferred to apply thecompounds of Formula I postemergence to relatively immature undesirablevegetation to achieve the maximum control of weeds.

Application rates of about 10 to about 1,000 g/Ha are generally employedin postemergence operations; for preemergence applications, rates ofabout 20 to about 2,000 g/Ha are generally employed. The higher ratesdesignated generally give non-selective control of a broad variety ofundesirable vegetation. The lower rates typically give selective controland can be employed in the locus of crops.

The herbicidal compounds of the present invention are often applied inconjunction with one or more other herbicides to control a wider varietyof undesirable vegetation. When used in conjunction with otherherbicides, the presently claimed compounds can be formulated with theother herbicide or herbicides, tank mixed with the other herbicide orherbicides or applied sequentially with the other herbicide orherbicides. Some of the herbicides that can be employed in conjunctionwith the compounds of the present invention include: amide herbicidessuch as allidochlor, beflubutamid, benzadox, benzipram, bromobutide,cafenstrole, CDEA, chlorthiamid, cyprazole, dimethenamid,dimethenamid-P, diphenamid, epronaz, etnipromid, fentrazamide, flupoxam,fomesafen, halosafen, isocarbamid, isoxaben, napropamide, naptalam,pethoxamid, propyzamide, quinonamid and tebutam; anilide herbicides suchas chloranocryl, cisanilide, clomeprop, cypromid, diflufenican,etobenzanid, fenasulam, flufenacet, flufenican, mefenacet, mefluidide,metamifop, monalide, naproanilide, pentanochlor, picolinafen andpropanil; arylalanine herbicides such as benzoylprop, flamprop andflamprop-M; chloroacetanilide herbicides such as acetochlor, alachlor,butachlor, butenachlor, delachlor, diethatyl, dimethachlor, metazachlor,metolachlor, S-metolachlor, pretilachlor, propachlor, propisochlor,prynachlor, terbuchlor, thenylchlor and xylachlor; sulfonanilideherbicides such as benzofluor, perfluidone, pyrimisulfan and profluazol;sulfonamide herbicides such as asulam, carbasulam, fenasulam andoryzalin; antibiotic herbicides such as bilanafos; benzoic acidherbicides such as chloramben, dicamba, 2,3,6-TBA and tricamba;pyrimidinyloxybenzoic acid herbicides such as bispyribac andpyriminobac; pyrimidinylthiobenzoic acid herbicides such as pyrithiobac;phthalic acid herbicides such as chlorthal; picolinic acid herbicidessuch as aminopyralid, clopyralid and picloram; quinolinecarboxylic acidherbicides such as quinclorac and quinmerac; arsenical herbicides suchas cacodylic acid, CMA, DSMA, hexaflurate, MAA, MAMA, MSMA, potassiumarsenite and sodium arsenite; benzoylcyclohexanedione herbicides such asmesotrione, sulcotrione, tefuryltrione and tembotrione; benzofuranylalkylsulfonate herbicides such as benfuresate and ethofumesate;carbamate herbicides such as asulam, carboxazole chlorprocarb,dichlormate, fenasulam, karbutilate and terbucarb; carbanilateherbicides such as barban, BCPC, carbasulam, carbetamide, CEPC,chlorbufam, chlorpropham, CPPC, desmedipham, phenisopham, phenmedipham,phenmedipham-ethyl, propham and swep; cyclohexene oxime herbicides suchas alloxydim, butroxydim, clethodim, cloproxydim, cycloxydim,profoxydim, sethoxydim, tepraloxydim and tralkoxydim;cyclopropylisoxazole herbicides such as isoxachlortole and isoxaflutole;dicarboximide herbicides such as benzfendizone, cinidon-ethyl, flumezin,flumiclorac, flumioxazin and flumipropyn; dinitroaniline herbicides suchas benfluralin, butralin, dinitramine, ethalfluralin, fluchloralin,isopropalin, methalpropalin, nitralin, oryzalin, pendimethalin,prodiamine, profluralin and trifluralin; dinitrophenol herbicides suchas dinofenate, dinoprop, dinosam, dinoseb, dinoterb, DNOC, etinofen andmedinoterb; diphenyl ether herbicides such as ethoxyfen; nitrophenylether herbicides such as acifluorfen, aclonifen, bifenox,chlomethoxyfen, chlomitrofen, etnipromid, fluorodifen, fluoroglycofen,fluoronitrofen, fomesafen, furyloxyfen, halosafen, lactofen, nitrofen,nitrofluorfen and oxyfluorfen; dithiocarbamate herbicides such asdazomet and metam; halogenated aliphatic herbicides such as alorac,chloropon, dalapon, flupropanate, hexachloroacetone, iodomethane, methylbromide, monochloroacetic acid, SMA and TCA; imidazolinone herbicidessuch as imazamethabenz, imazamox, imazapic, imazapyr, imazaquin andimazethapyr; inorganic herbicides such as ammonium sulfamate, borax,calcium chlorate, copper sulfate, ferrous sulfate, potassium azide,potassium cyanate, sodium azide, sodium chlorate and sulfuric acid;nitrile herbicides such as bromobonil, bromoxynil, chloroxynil,dichlobenil, iodobonil, ioxynil and pyraclonil; organophosphorusherbicides such as amiprofos-methyl, anilofos, bensulide, bilanafos,butamifos, 2,4-DEP, DMPA, EBEP, fosamine, glufosinate, glyphosate andpiperophos; phenoxy herbicides such as bromofenoxim, clomeprop, 2,4-DEB,2,4-DEP, difenopenten, disul, erbon, etnipromid, fenteracol andtrifopsime; phenoxyacetic herbicides such as 4-CPA, 2,4-D, 3,4-DA, MCPA,MCPA-thioethyl and 2,4,5-T; phenoxybutyric herbicides such as 4-CPB,2,4-DB, 3,4-DB, MCPB and 2,4,5-TB; phenoxypropionic herbicides such ascloprop, 4-CPP, dichlorprop, dichlorprop-P, 3,4-DP, fenoprop, mecopropand mecoprop-P; aryloxyphenoxypropionic herbicides such as chlorazifop,clodinafop, clofop, cyhalofop, diclofop, fenoxaprop, fenoxaprop-P,fenthiaprop, fluazifop, fluazifop-P, haloxyfop, haloxyfop-P,isoxapyrifop, metamifop, propaquizafop, quizalofop, quizalofop-P andtrifop; phenylenediamine herbicides such as dinitramine and prodiamine;pyrazolyl herbicides such as benzofenap, pyrazolynate, pyrasulfotole,pyrazoxyfen, pyroxasulfone and topramezone; pyrazolylphenyl herbicidessuch as fluazolate and pyraflufen; pyridazine herbicides such ascredazine, pyridafol and pyridate; pyridazinone herbicides such asbrompyrazon, chloridazon, dimidazon, flufenpyr, metflurazon,norflurazon, oxapyrazon and pydanon; pyridine herbicides such asaminopyralid, cliodinate, clopyralid, dithiopyr, fluroxypyr, haloxydine,picloram, picolinafen, pyriclor, thiazopyr and triclopyr;pyrimidinediamine herbicides such as iprymidam and tioclorim; quaternaryammonium herbicides such as cyperquat, diethamquat, difenzoquat, diquat,morfamquat and paraquat; thiocarbamate herbicides such as butylate,cycloate, di-allate, EPTC, esprocarb, ethiolate, isopolinate,methiobencarb, molinate, orbencarb, pebulate, prosulfocarb,pyributicarb, sulfallate, thiobencarb, tiocarbazil, tri-allate andvernolate; thiocarbonate herbicides such as dimexano, EXD and proxan;thiourea herbicides such as methiuron; triazine herbicides such asdipropetryn, triaziflam and trihydroxytriazine; chlorotriazineherbicides such as atrazine, chlorazine, cyanazine, cyprazine,eglinazine, ipazine, mesoprazine, procyazine, proglinazine, propazine,sebuthylazine, simazine, terbuthylazine and trietazine; methoxytriazineherbicides such as atraton, methometon, prometon, secbumeton, simetonand terbumeton; methylthiotriazine herbicides such as ametryn,aziprotryne, cyanatryn, desmetryn, dimethametryn, methoprotryne,prometryn, simetryn and terbutryn; triazinone herbicides such asametridione, amibuzin, hexazinone, isomethiozin, metamitron andmetribuzin; triazole herbicides such as amitrole, cafenstrole, epronazand flupoxam; triazolone herbicides such as amicarbazone, bencarbazone,carfentrazone, flucarbazone, propoxycarbazone, sulfentrazone andthiencarbazone-methyl; triazolopyrimidine herbicides such ascloransulam, diclosulam, florasulam, flumetsulam, metosulam, penoxsulamand pyroxsulam; uracil herbicides such as butafenacil, bromacil,flupropacil, isocil, lenacil and terbacil; 3-phenyluracils; ureaherbicides such as benzthiazuron, cumyluron, cycluron, dichloralurea,diflufenzopyr, isonoruron, isouron, methabenzthiazuron, monisouron andnoruron; phenylurea herbicides such as anisuron, buturon, chlorbromuron,chloreturon, chlorotoluron, chloroxuron, daimuron, difenoxuron,dimefuron, diuron, fenuron, fluometuron, fluothiuron, isoproturon,linuron, methiuron, methyldymron, metobenzuron, metobromuron, metoxuron,monolinuron, monuron, neburon, parafluron, phenobenzuron, siduron,tetrafluron and thidiazuron; pyrimidinylsulfonylurea herbicides such asamidosulfuron, azimsulfuron, bensulfuron, chlorimuron, cyclosulfamuron,ethoxysulfuron, flazasulfuron, flucetosulfuron, flupyrsulfuron,foramsulfuron, halosulfuron, imazosulfuron, mesosulfuron, nicosulfuron,orthosulfamuron, oxasulfuron, primisulfuron, pyrazosulfuron,rimsulfuron, sulfometuron, sulfosulfuron and trifloxysulfuron;triazinylsulfonylurea herbicides such as chlorsulfuron, cinosulfuron,ethametsulfuron, iodosulfuron, metsulfuron, prosulfuron, thifensulfuron,triasulfuron, tribenuron, triflusulfuron and tritosulfuron;thiadiazolylurea herbicides such as buthiuron, ethidimuron, tebuthiuron,thiazafluron and thidiazuron; and unclassified herbicides such asacrolein, allyl alcohol, azafenidin, benazolin, bentazone,benzobicyclon, buthidazole, calcium cyanamide, cambendichlor,chlorfenac, chlorfenprop, chlorflurazole, chlorflurenol, cinmethylin,clomazone, CPMF, cresol, ortho-dichlorobenzene, dimepiperate, endothal,fluoromidine, fluridone, flurochloridone, flurtamone, fluthiacet,indanofan, methazole, methyl isothiocyanate, nipyraclofen, OCH,oxadiargyl, oxadiazon, oxaziclomefone, pentachlorophenol, pentoxazone,phenylmercury acetate, pinoxaden, prosulfalin, pyribenzoxim, pyriftalid,quinoclamine, rhodethanil, sulglycapin, thidiazimin, tridiphane,trimeturon, tripropindan and tritac. The herbicidal compounds of thepresent invention can, further, be used in conjunction with glyphosate,glufosinate, dicamba or 2,4-D on glyphosate-tolerant,glufosinate-tolerant, dicamba-tolerant or 2,4-D-tolerant crops. It isgenerally preferred to use the compounds of the invention in combinationwith herbicides that are selective for the crop being treated and whichcomplement the spectrum of weeds controlled by these compounds at theapplication rate employed. It is further generally preferred to applythe compounds of the invention and other complementary herbicides at thesame time, either as a combination formulation or as a tank mix.

The compounds of the present invention can generally be employed incombination with known herbicide safeners, such as benoxacor,benthiocarb, brassinolide, cloquintocet(mexyl), cyometrinil, daimuron,dichlormid, dicyclonon, dimepiperate, disulfoton, fenchlorazole-ethyl,fenclorim, flurazole, fluxofenim, furilazole, isoxadifen-ethyl,mefenpyr-diethyl, MG 191, MON 4660, naphthalic anhydride (NA),oxabetrinil, R29148 and N-phenyl-sulfonylbenzoic acid amides, to enhancetheir selectivity. They can additionally be employed to controlundesirable vegetation in many crops that have been made tolerant to orresistant to them or to other herbicides by genetic manipulation or bymutation and selection. For example, corn, wheat, rice, soybean,sugarbeet, cotton, canola, and other crops that have been made tolerantor resistant to compounds that are acetolactate synthase inhibitors insensitive plants can be treated. Many glyphosate and glufosinatetolerant crops can be treated as well, alone or in combination withthese herbicides. Some crops (e.g. cotton) have been made tolerant toauxinic herbicides such as 2,4-dichlorophenoxyacetic acid. Theseherbicides may be used to treat such resistant crops or other auxintolerant crops.

While it is possible to utilize the 2-(substituted phenyl)-6-hydroxy oralkoxy-5-substituted-4-pyrimidinecarboxylate compounds of Formula Idirectly as herbicides, it is preferable to use them in mixturescontaining an herbicidally effective amount of the compound along withat least one agriculturally acceptable adjuvant or carrier. Suitableadjuvants or carriers should not be phytotoxic to valuable crops,particularly at the concentrations employed in applying the compositionsfor selective weed control in the presence of crops, and should notreact chemically with the compounds of Formula I or other compositioningredients. Such mixtures can be designed for application directly toweeds or their locus or can be concentrates or formulations that arenormally diluted with additional carriers and adjuvants beforeapplication. They can be solids, such as, for example, dusts, granules,water dispersible granules, or wettable powders, or liquids, such as,for example, emulsifiable concentrates, solutions, emulsions orsuspensions.

Suitable agricultural adjuvants and carriers that are useful inpreparing the herbicidal mixtures of the invention are well known tothose skilled in the art.

Liquid carriers that can be employed include water, toluene, xylene,petroleum naphtha, crop oil, acetone, methyl ethyl ketone,cyclohexanone, trichloroethylene, perchloroethylene, ethyl acetate, amylacetate, butyl acetate, propylene glycol monomethyl ether and diethyleneglycol monomethyl ether, methanol, ethanol, isopropanol, amyl alcohol,ethylene glycol, propylene glycol, glycerine, N-methyl-2-pyrrolidinone,N,N-dimethyl alkylamides, liquid fertilizers and the like. Water isgenerally the carrier of choice for the dilution of concentrates.

Suitable solid carriers include talc, pyrophyllite clay, silica,attapulgus clay, kaolin clay, kieselguhr, chalk, diatomaceous earth,lime, calcium carbonate, bentonite clay, Fuller's earth, cotton seedhulls, wheat flour, soybean flour, pumice, wood flour, walnut shellflour, lignin, and the like.

It is usually desirable to incorporate one or more surface-active agentsinto the compositions of the present invention. Such surface-activeagents are advantageously employed in both solid and liquidcompositions, especially those designed to be diluted with carrierbefore application. The surface-active agents can be anionic, cationicor nonionic in character and can be employed as emulsifying agents,wetting agents, suspending agents, or for other purposes. Typicalsurface-active agents include salts of alkyl sulfates, such asdiethanol-ammonium lauryl sulfate; alkylarylsulfonate salts, such ascalcium dodecyl-benzenesulfonate; alkylphenol-alkylene oxide additionproducts, such as nonylphenol-C₁₈ ethoxylate; alcohol-alkylene oxideaddition products, such as tridecyl alcohol-C₁₆ ethoxylate; soaps, suchas sodium stearate; alkylnaphthalene-sulfonate salts, such as sodiumdibutylnaphthalenesulfonate; dialkyl esters of sulfosuccinate salts,such as sodium di(2-ethylhexyl)sulfosuccinate; sorbitol esters, such assorbitol oleate; quaternary amines, such as lauryl trimethyl-ammoniumchloride; polyethylene glycol esters of fatty acids, such aspoly-ethylene glycol stearate; block copolymers of ethylene oxide andpropylene oxide; and salts of mono and dialkyl phosphate esters.

Other adjuvants commonly used in agricultural compositions includecompatibilizing agents, antifoam agents, sequestering agents,neutralizing agents and buffers, corrosion inhibitors, dyes, odorants,spreading agents, penetration aids, sticking agents, dispersing agents,thickening agents, freezing point depressants, antimicrobial agents, andthe like. The compositions may also contain other compatible components,for example, other herbicides, plant growth regulants, fungicides,insecticides, and the like and can be formulated with liquid fertilizersor solid, particulate fertilizer carriers such as ammonium nitrate, ureaand the like.

The concentration of the active ingredients in the herbicidalcompositions of this invention is generally from about 0.001 to about 98percent by weight. Concentrations from about 0.01 to about 90 percent byweight are often employed. In compositions designed to be employed asconcentrates, the active ingredient is generally present in aconcentration from about 5 to about 98 weight percent, preferably about10 to about 90 weight percent. Such compositions are typically dilutedwith an inert carrier, such as water, before application. The dilutedcompositions usually applied to weeds or the locus of weeds generallycontain about 0.0001 to about 1 weight percent active ingredient andpreferably contain about 0.001 to about 0.05 weight percent.

The present compositions can be applied to weeds or their locus by theuse of conventional ground or aerial dusters, sprayers, and granuleapplicators, by addition to irrigation water, and by other conventionalmeans known to those skilled in the art.

The following Examples are presented to illustrate the various aspectsof this invention and should not be construed as limitations to theclaims.

EXAMPLES 1. Preparation of6-hydroxy-2-(4-chloro-2-fluoro-3-methoxyphenyl)-5-chloropyrimidine-4-carboxylicacid methyl ester (Compound 1)

6-Amino-2-(4-chloro-2-fluoro-3 -methoxyphenyl)-5-chloropyrimidine-4-carboxylic acid methyl ester (320 mg, 0.92 mmol, seeU.S. Pat. No. 7,300,907 B2 for preparation) was dissolved in 10 mL 1MH₂SO₄ plus 4 mL acetonitrile, warmed to 75° C. and treated in portionswith sodium nitrite (690 mg, 10 mmol) over 30 minutes. After stirringfor 10 minutes more the mixture was cooled and the solid product wascollected by filtration, washed well with water, and dried under vacuumat 80° C. to give 170 mg (53% yield) of6-hydroxy-2-(4-chloro-2-fluoro-3-methoxyphenyl)-5-chloropyrimidine-4-carboxylicacid methyl ester MP 215-217° C.; MS m/z 346; ¹H NMR (DMSO-d₆): δ 7.47 (m, 2H), 3.94(s, 3H), 3.91(s, 3H), 3.34(br s, 1H).

2. Preparation of6-hydroxy-2-(4-chloro-2-fluoro-3-methoxyphenyl)-pyrimidine-4-carboxylicacid methyl ester

6-Amino-2-(4-chloro-2-fluoro-3-methoxyphenyl)pyrimidine-4-carboxylicacid methyl ester (300 mg, 0.97 mmol, see U.S. Pat. No.7,300,907 B2 forpreparation) was slurried in 10 mL 1M H₂SO₄ plus 3 mL acetonitrile,heated to 75° C. and treated in portions with sodium nitrite (350 mg, 5mmol) over a period of 10 minutes. After 40 minutes the mixture wascooled and the yellow precipitate was taken up in 40 mL ethyl acetate,washed with 10 mL water, washed with 10 mL brine, dried, and evaporatedto give 170 mg (60% yield)6-hydroxy-2-(4-chloro-2-fluoro-3-methoxyphenyl)pyrimidine-4-carboxylicacid methyl ester; MS m/z 312, ¹H NMR (DMSO-d₆): δ 7.49(m, 3H),3.95(s,3H), 3.86(s, 3H)

3. Preparation of6-hydroxy-2-(4-chloro-2-fluoro-3-methoxyphenyl)-5-bromopyrimidine-4-carboxylicacid methyl ester (Compound 2)

6-Hydroxy-2-(4-chloro-2-fluoro-3-methoxyphenyl)pyrimidine-4-carboxylicacid methyl ester(150 mg, 0.48 mmol) was combined withN-bromosuccinimide (180 mg, 1.0 mmol) in 7 mL dichloromethane plus 2 mLacetonitrile and heated to reflux for 2 hours. After cooling thevolatiles were removed under vacuum and the residue was taken up in 15mL dichloromethane plus 5 mL water. The organic phase was separated andwashed with 10 mL 5% sodium bisulfite solution, washed with 10 mL brine,dried and evaporated to give 120 mg (63% yield) of6-hydroxy-2-(4-chloro-2-fluoro-3-methoxyphenyl)-5-bromopyrimidine-4-carboxylicacid methyl ester: mp 192-195° C.; MS m/z 390/392; ¹H NMR (DMSO-d₆): δ7.47(m, 3H), 3.95(d, 3H), 3.91(s,3H)

4. Preparation of6-hydroxy-2-(4-chloro-2-fluoro-3-methoxyphenyl)-5-methoxypyrimidine-4-carboxylicacid methyl ester (Compound 3)

6-Amino-2-(4-chloro-2-fluoro-3 -methoxyphenyl)-5-methoxypyrimidine-4-carboxylic acid methyl ester (200 mg, 0.61 mmol)was dissolved in 20 mL of 9 molar H₂SO₄ plus 5 mL acetonitrile andtreated in portions with NaNO₂ (150 mg, 2.2 mmol). After the additionwas complete, the mixture was stirred for 30 minutes at 25° C., cooledin ice-salt and treated carefully with 50% NaOH to bring the pH to ca0.8. The precipitate was taken up by extracting with two 15 mL portionsof EtOAc and the combined extracts were washed with 10 mL sat. NaCl,dried (Na₂SO₄) and evaporated to give the title product 150 mg (75%).Mp: 177-179° C. MS m/z 342; ¹H NMR (DMSO-d₆): δ 7.81 (m, 1H), 7.31 (m,1H), 4.05(s, 3H), 4.01(s, 3H).

5. Preparation of Herbicidal Compositions

In the following illustrative compositions, parts and percentages are byweight.

Emulsifiable Concentrates Formulation A

WT % Compound 1 26.2 Polyglycol 26-3 5.2 Nonionicemulsifier-(di-sec-butyl)- phenyl-poly(oxypropylene)block polymer with(oxyethylene). The polyoxyethelene content is about 12 moles. WitconateP12-20 (Anionic emulsifier- 5.2 calcium dodecylbenzene sulfonate- 60 wt.% active) Aromatic 100 (Xylene range aromatic 63.4 solvent)

Formulation B

WT % Compound 1 3.5 Sunspray 11N (paraffin oil) 40.0 Polyglycol 26-319.0 Oleic acid 1.0 Xylene range aromatic solvent 36.5

Formulation C

WT % Compound 2 13.2 Stepon C-65 25.7 Ethomeen T/25 7.7 Ethomeen T/1518.0 Xylene range aromatic solvent 35.4

Formulation D

WT % Compound 1 30.0 Agrimer A1-10LC (emulsifier) 3.0N-methyl-2-pyrrolidone 67.0

Formulation E

WT % Compound 2 10.0 Agrimul 70-A (dispersant) 2.0 Amsul DMAP 60(thickener) 2.0 Emulsogen M (emulsifier) 8.0 Attagel 50 (suspension aid)2.0 Crop oil 76.0

These concentrates can be diluted with water to give emulsions ofsuitable concentrations for controlling weeds.

Wettable Powders Formulation F

WT % Compound 1 26.0 Polyglycol 26-3 2.0 Polyfon H 4.0 Zeosyl 100(Precipitated hydrated SiO₂) 17.0 Barden clay + inerts 51.0

Formulation G

WT % Compound 1 62.4 Polyfon H (sodium salt of lignin 6.0 sulfonate)Sellogen HR (sodium naphthalene 4.0 sulfonate) Zeosyl 100 27.6

Formulation H

WT % Compound 1 1.4 Kunigel V1 (carrier) 30.0 Stepanol ME Dry (wetter)2.0 Tosnanon GR 31A (binder) 2.0 Kaolin NK-300 Clay (filler) 64.6

The active ingredient is applied to the corresponding carriers and thenthese are mixed and ground to yield wettable powders of excellentwettability and suspension power. By diluting these wettable powderswith water it is possible to obtain suspensions of suitableconcentrations for controlling weeds.

Water Dispersible Granules Formulation I

WT % Compound 1 26.0 Sellogen HR 4.0 Polyfon H 5.0 Zeosyl 100 17.0Kaolinite clay 48.0

The active ingredient is added to the hydrated silica, which is thenmixed with the other ingredients and ground to a powder. The powder isagglomerated with water and sieved to provide granules in the range of−10 to +60 mesh. By dispersing these granules in water it is possible toobtain suspensions of suitable concentrations for controlling weeds.

Granules Formulation J

WT % Compound 1 5.0 Celetom MP-88 95.0

The active ingredient is applied in a polar solvent such asN-methylpyrollidinone, cyclohexanone, gamma-butyrolactone, etc. to theCeletom MP 88 carrier or to other suitable carriers. The resultinggranules can be applied by hand, granule applicator, airplane, etc. inorder to control weeds.

Formulation K

WT % Compound 1 1.0 Polyfon H 8.0 Nekal BA 77 2.0 Zinc Stearate 2.0Barden Clay 87.0

All materials are blended and ground to a powder then water is added andthe clay mixture is stirred until a paste is formed. The mixture isextruded through a die to provide granules of proper size.

6. Evaluation of General Postemergence Herbicidal Activity

Seeds or nutlets of the desired test plant species were planted in SunGro MetroMix® 306 planting mixture, which typically has a pH of 6.0 to6.8 and an organic matter content of about 30 percent, in plastic potswith a surface area of 64 square centimeters. When required to ensuregood germination and healthy plants, a fungicide treatment and/or otherchemical or physical treatment was applied. The plants were grown for7-21 days in a greenhouse with an approximate 15 hour photoperiod whichwas maintained at about 23-29° C. during the day and 22-28° C. duringthe night. Nutrients and water were added on a regular basis andsupplemental lighting was provided with overhead metal halide 1000-Wattlamps as necessary. The plants were employed for testing when theyreached the first or second true leaf stage.

A weighed amount, determined by the highest rate to be tested, of eachtest compound was dissolved in 4 mL of a 97:3 v/v (volume/volume)mixture of acetone and dimethyl sulfoxide (DMSO) to obtain concentratedstock solutions. If the test compound did not dissolve readily, themixture was warmed and/or sonicated. The concentrated stock solutionsobtained were diluted with 20 mL of an aqueous mixture containingacetone, water, isopropyl alcohol, DMSO, Atplus 411F crop oilconcentrate, and Triton® X-155 surfactant in a 48.5:39:10:1.5:1.0:0.02v/v ratio to obtain spray solutions containing the highest applicationrates. Additional application rates were obtained by serial dilution of12 mL of the high rate solution into a solution containing 2 mL of 97:3v/v (volume/volume) mixture of acetone and dimethyl sulfoxide (DMSO) and10 mL of an aqueous mixture containing acetone, water, isopropylalcohol, DMSO, Atplus 411F crop oil concentrate, and Triton X-155surfactant in a 48.5:39:10:1.5:1.0:0.02 v/v ratio to obtain 1/2X, 1/4X,1/8X and 1/16X rates of the high rate. Compound requirements are basedupon a 12 mL application volume at a rate of 187 L/ha. Formulatedcompounds were applied to the plant material with an overhead Mandeltrack sprayer equipped with a 8002E nozzles calibrated to deliver 187L/ha over an application area of 0.503 square meters at a spray heightof 18 inches (43 cm) above the average plant canopy height. Controlplants were sprayed in the same manner with the solvent blank.

The treated plants and control plants were placed in a greenhouse asdescribed above and watered by sub-irrigation to prevent wash-off of thetest compounds. After 14 days, the condition of the test plants ascompared with that of the untreated plants was determined visually andscored on a scale of 0 to 100 percent where 0 corresponds to no injuryand 100 corresponds to complete kill.

Some of the compounds tested, application rates employed, plant speciestested, and results are given in Table 1.

TABLE 1 Post-emergent Weed Control Rate % Growth Reduction Compound gai/ha CHEAL AMARE EPHHL HELAN 1 280 100  100 100 90 2 280 95 100 100 853 280 90  40 100 10 CHEAL - Lambsquarters (Chenopodium album) AMARE -Redroot Pigweed (Amatanthus retroflexus) EPHHL - Wild Pointsettia(Euphorbia heterophylla) HELAN - Common Sunflower (Helianthus annuus)

1. A compound of the formula I

wherein Q represents a halogen, cyano, C₁-C₄ alkyl, C₁-C₄ haloalkyl,C₂-C₄ alkenyl and epoxides thereof, C₂-C₄ haloalkenyl and epoxidesthereof, C₂-C₄ alkynyl, C₂-C₄ haloalkynyl, C₁-C₄ alkoxy, C₁-C₄haloalkoxy, C₁-C₄ alkylthio or C₁-C₄ haloalkylthio; R₁ represents H orC₁-C₄ alkyl; W represents H or halogen; X represents H or halogen; Yrepresents halogen, C₁-C₄ alkyl, C₁-C₄ alkoxy, C₁-C₄ alkylthio, C₁-C₄haloalkyl, C₁-C₄ haloalkoxy, C₁-C₄ haloalkylthio, —NR₂R₃, C₁-C₄alkoxy-substituted C₁-C₄ alkyl, C₁-C₄ haloalkoxy-substituted C₁-C₄alkyl, C₂-C₄ alkenyl, C₂-C₄ haloalkenyl or C₁-C₄ haloalkyl-substitutedcarbonyl; Z represents halogen, C₁-C₄ alkyl or C₁-C₄ haloalkyl; and R₂and R₃ independently represent H or C₁-C₄ alkyl; and agriculturallyacceptable derivatives of the carboxylic acid group.
 2. A compound ofclaim 1 in which the agriculturally acceptable derivatives of thecarboxylic acid group are agriculturally acceptable salts, esters andamides.
 3. A compound of claim 1 in which Q represents Cl, Br, C₂-C₄alkenyl or C₁-C₄ alkoxy; R₁ represents H; W represents H; X represents Hor F; Y represents F or OCH₃; and Z represents Cl.
 4. A herbicidalcomposition comprising a herbicidally effective amount of a compound ofFormula I, according to claim 1, in a mixture with an agriculturallyacceptable adjuvant or carrier.
 5. A method of controlling undesirablevegetation which comprises contacting the vegetation or the locusthereof with or applying to the soil to prevent the emergence ofvegetation an herbicidally effective amount of a compound of Formula I,according to claim 1.